POSEIDON Examples

Ernesto

February, 2018

Policy-making with POSEIDON

  • Understanding incentives
  • Controlling incentives
  • Improving Policy

Nudging targets

  • 200 Fishers
  • 2 Species of fish:
    • Expensive Blue
    • Cheap Red
  • Selective Gear

No policy

Policy

  • Problem:
    • Expensive stock being depleted
    • Long term loss of profitability
  • Constraints:
    • Cannot enforce gear switch
    • Cannot remove fishers
  • Question:
    • Can we tax blue or subsidize red to maximize long term profits?

Model for scenario evaluation

  • Ban blue landings when stock below a threshold

Model for optimization

  • Find % tax on blue to maximize 30-years profits

Fine-tuning ways and means

  • New Objective:
    • Need to land approximately 600 blue fish a day
  • Problem:
    • Fixed tax will not work
  • Question:
    • Can we adjust incentives depending on landings?

Difficult Problem

Complicated Solutions

Complicated Solutions 2

Winners and Losers

  • One species of fish
  • Two kinds of fishers:
    • Large Commercial Vessels
    • Small Fishing Boats
  • Problem:
    • Overfishing

Winners and Losers (2)

Policy

  • Problem:
    • Overfishing
    • Low profits for small fishermen
  • Constraints:
    • Cannot regulate small boats
    • Cannot enforce quotas
    • Can only implement one MPA
  • Question:
    • Where should we place this MPA?
    • Who wins and who loses?

Pareto Front

Leftmost Solution

Rightmost Solution

Buyouts

  • New Constraint:
    • We cannot impose any MPA
    • We can only buy large vessels out of the market
  • Question:
    • How many should we buy?

Scenario Evaluation